Receivers employing DSP perform mixing and filtering in the digital domain. The cost of implementing a particular receiver using DSP components increases with the amount of processing required to perform the desired functions. The processing load of a particular DSP system depends on the functions implemented and on the complexity of the implementation of these functions.
In a receiver employing DSP, a received band-limited analog signal is sampled to produce a digital signal that is processed using DSP circuits. The received band limited analog-signal is sampled at a rate of two or more times higher than the bandwidth of the signal. The sampled signal is translated to a lower center frequency in the DSP circuits to allow further processing to be performed at a lower sampling rate. Decimation is a technique used to reduce the sampling rate of incoming signal to a receiver. Reduction in the cost of processing digital signals in various implementations of digital signal processing systems is desired.